1 . 如图,在三棱锥
中,已知
,
,
,
,
,
.
为
的中点,求证:
;
(2)求平面
与平面
夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41e5db1d2fd912f77923e4c120a7dc19.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/080ca48cd27d4bf9d9ef084b558fc17a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef0402dd5ae3db10281f9f1e11738bcb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ce64044898d0460aac161d93a455304.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba8c340f8945083d2993ff28eabfcccf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4d6b27a35a18492e60b5b99789d3395.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45acdbac251ca6b76a166c1242e71df9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c177e06cc3f703e8ca7be7c491fa2942.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cc6f6dfdbe7d39891c35f67e1a95c7f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21665d21bbfb04410c78345de1fd15ae.png)
您最近一年使用:0次
名校
2 . 已知
,下列四个结论:①
,②
,③
,④
.其中错误的个数是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e1bb486cbf98ae341a35a17e79fae7d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7b0e6eb011614deef2d50ceab01c8d1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7e0b26fa1a2c42bf24833e241ea25a3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ec504e75b5fe6435a94047a2f0b9443.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9dd82388f903f53c58ff6d655dd7d14.png)
A.1 | B.2 | C.3 | D.4 |
您最近一年使用:0次
3 . 已知双曲线
:
的左,右焦点分别为
,
,过
的直线与双曲线
的右支交于
,
两点,且
,则
的周长为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9a0bd4bd9985f1e367c100b453ed03f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5076289823db419f94e9c0c8f4aafd9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3fb78c5f885034612c0e030b920143d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3fb78c5f885034612c0e030b920143d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0907a673d52825cd7df84b400972d4b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/47ff8a5886e42095da57422c8777c10d.png)
A.20 | B.22 | C.28 | D.36 |
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4 . 下列叙述中,是离散型随机变量的是( )
A.某电子元件的寿命 |
B.某人早晨在车站等出租车的时间 |
C.高速公路上某收费站在一小时内经过的车辆数 |
D.测量某零件的长度产生的测量误差 |
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5 . 3600的正因数的个数是( )
A.55 | B.50 | C.45 | D.40 |
您最近一年使用:0次
解题方法
6 . 在平面直角坐标系
中,已知直线
:
与圆
:
交于
两点,则
的最大值为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ee31829d0d4d5f779a957d7df8058ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da08d6d27b6cf7ee1a9f49737bbb70de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a324c816e299f545ba3f31d37544d07d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01c74a907dda6bb7d9d56d009d9df253.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a704469569b68ee11ab166dba3f686f0.png)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
解题方法
7 . 已知正方体
的棱长为2,点M,N分别为棱
的中点,点
为四边形
(含边界)内一动点,且
,则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b53e1d6a86a36dd76b41004af795d901.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/632f2bf1cd0435041fa04b01901d1c8c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a7967ac1132d836e6a2ca6af5790521.png)
A.![]() ![]() |
B.点![]() ![]() |
C.存在点![]() ![]() ![]() |
D.点![]() ![]() ![]() |
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8 . 函数
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f46db9383bbe209ae9ead101a42e6569.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/427c7d45f28e6efae087669055b4658d.png)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
名校
解题方法
9 . 已知函数
的导函数为
,且
,当
时,
,则不等式
的解集为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fe7d5809da02c15a43a0e9a898b9086.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a4b04824a308519a61318a82aa97a05.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e91770acb583f05c3ead767d247be034.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08115d6d9f876dea921a4d32260ff1fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7d09afb1e101b1556179200f9a59d23a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f12e34de335c69e51876e9447659aa40.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
您最近一年使用:0次
解题方法
10 . 已知锐角
满足
,
.
(1)求
的值;
(2)求
的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4e288596fa3811dd2c17bded60e82e7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58b291445e61f53061200d5d0d31f678.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51ddab84f6c20c4f398b59a815ee2aec.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/52ac5ed81371243d3b7b69b21c6f0611.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8dc4c63a548b91061528aa11058de75.png)
您最近一年使用:0次